Stock was born in Jülich, Germany and given his early musical education by his army bandmaster father. At the age of fourteen, Frederick Stock was admitted into the Cologne Conservatory as a student of violin and composition, where he counted Engelbert Humperdinck as one of his teachers, and Willem Mengelberg among his classmates. After graduating from the conservatory in 1890, Stock was accepted to the Municipal Orchestra of Cologne as a violinist. In 1895, Stock met with Theodore Thomas, founder and first music director of the then fledgling Chicago Orchestra and the man who was to have a decisive impact on Stock's future. Thomas, who was then visiting Germany in search of recruits for his Chicago Orchestra, auditioned Stock and gave him a position as violist in the orchestra. Thomas soon realized, however, that his new violist was also a very talented conductor and in 1899, Stock was promoted to assistant conductor. After the death of Theodore Thomas on January 4, 1905, Frederick Stock took over the immediate duties of music director. That year, he wrote a symphonic poem Eines Menschenlebens Morgen, Mittag, und Abend, dedicated to "Theodore Thomas and the Members of the Chicago Orchestra." The work was first performed on April 7 and 8, 1905. Initially, the board of trustees approached Hans Richter, Felix Weingartner, and Felix Mottl to succeed Thomas. However, the board's executive committee met on April 11, 1905, and resolved: "Frederick Stock unanimously elected Conductor. Trustees voted that the Orchestra should now be known as 'The Theodore Thomas Orchestra.' (The ensemble's name was ultimately changed to Chicago Symphony Orchestra in 1913.) Under Stock's direction, the Chicago Symphony Orchestra became one of America's top orchestras, developing a distinctive brass sound that can already be heard in the orchestra's first recordings. An enthusiast of modern music, Stock championed the works of many then modern composers including Gustav Mahler; Richard Strauss (who, at Theodore Thomas's invitation, had been the CSO's first-ever guest conductor on subscription concerts in April 1904); Stravinsky, whose Symphony in C was commissioned for the orchestra's 50th anniversary; Sergei Prokofiev, who was soloist in the world premiere of his Third Piano Concerto in Chicago; Gustav Holst; Zoltán Kodály, whose Concerto for Orchestra was commissioned by Stock; Nikolai Myaskovsky; Josef Suk; William Walton; Arthur Benjamin; George Enescu; and many others. Frederick Stock's thirty-seven year tenure as head of the Chicago Symphony Orchestra was surpassed in America only by Eugene Ormandy's lengthy directorship of the Philadelphia Orchestra. Soon after Stock's death in Chicago on 20 October 1942, Désiré Defauw was chosen as his successor. In 1936, when Stock was less and less able to conduct himself, Hans Lange, formerly assistant of Toscanini in New York, was hired as conductor at CSO. He remained at CSO also during Defauw's tenure and was one of the mentors of Chicago composer Leon Stein.